workflow to filter out several folders from a git repo.

shell.sh

git clone example.com:/url/to/project.git
cd project
# these next few commands show how to rename branch "mybranch" to master
git checkout mybranch
git branch -d master
git checkout -b master
git branch -d mybranch
# remove orgin to make sure we don't accidentally do anything there
git remote rm origin
# none of the tags apply to mybranch
git tag -l | xargs git tag -d
# this version didn't work
#git filter-branch --index-filter "git rm -r -f --cached --ignore-unmatch $(ls -xd common/!(classes) common/!(includes) html/!(webtools) includes/!(webtools))" --prune-empty -- --all
# use the greps to exclude what you want to keep
# BUG: this doesn't filer out files with spaces in them
git filter-branch --prune-empty \
  --index-filter 'git ls-tree -r --name-only --full-tree $GIT_COMMIT | \
  egrep -v "^lib/(library1|library2)" | \
  grep -v "^app/includes" | \
  grep -v "^data/myapp" | \
  xargs git rm --cached --ignore-unmatch -r -f' -- --all
# BUG: If it doesn't filter out files with spaces you can use something like
# the following. Note here you are specifying the files you want to delete
# instead of excluding what you don't want.
git filter-branch --force --index-filter 'git rm -r -f --cached --ignore-unmatch "data/content with spaces.txt' --prune-empty -- --all
# Next 4 commands remove all the old history for good from local repo
git reset --hard
git for-each-ref --format="%(refname)" refs/original/ | xargs -n 1 git update-ref -d
git reflog expire --expire=now --all
git gc --prune=now
# Now add the origin to new project name and push it
git remote add origin example.com:/url/to/project2.git
git push -u origin master